CAUTION
Do not operate your system without Digital-supplied module covers.
They are required to protect the equipment and to meet international
regulatory standards. Do not substitute other module covers as they may
not meet the required specifications.
Operating your system without the module covers has the following
consequences.
• The system may overheat due to improper air circulation.
• The system will not comply with FCC and VDE requirements for
electromagnetic shielding and may produce electrical interference that
affects other equipment.
• The system is susceptible to electrical interference or damage from
external sources.
The design of module covers varies, depending on the type of module installed in
each slot.
• Modules requiring external cable connections, such as communication
controllers, have recessed covers that are riveted directly to the module.
The recessed covers provide space for connecting cables.
• Modules requiring no external cable connections, such as mass storage
controllers, are covered by flush covers. Empty slots are also covered by flush
covers which may be single or double width.
All covers, except those covering empty slots, have a label identifying the module
installed in the slot.
Cables connecting your system to peripheral devices (such as terminals, modems,
and printers) are attached to communication controllers. Each cable can contain
multiple lines. The cables run under the system and out the back or side, where
they are split into individual lines. Chapter 3 describes those connections in more
detail.
System Overview 1–11
